Getting the measure of noise

Researchers at the

(NIST) and industry collaborators have developed improved methods for accurately measuring very faint thermal “noise”—caused by random motion of electrons—in electronic circuits.

The technique may help improve the signal range, data rate and battery life of cell phones and other wireless communications devices.

According to NIST, low background noise typically translates to better performance in electronics, such as longer ranges and clearer signals or higher information-carrying capacity. However, noise too low to measure means that circuit designers cannot tune the system for optimal performance.

The NIST research focuses on CMOS (complementary metal oxide semiconductor) transistors, which are inexpensive and widely used in integrated circuits for wireless devices. Noise levels for CMOS transistors have, until now, been too low to measure accurately in much of their signal frequency range (1 – 10 gigahertz), and as a result CMOS circuits may be poorly matched to wireless transmission systems, resulting in significant signal loss.